/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 * 
 * Author: Adam Dunkels <adam@sics.se>
 *
 */
#ifndef __LWIP_UDP_H__
#define __LWIP_UDP_H__

#include "lwip/opt.h"

#if LWIP_UDP			/* don't build if not configured for use in lwipopts.h */

#include "lwip/pbuf.h"
#include "lwip/netif.h"
#include "lwip/ip_addr.h"
#include "lwip/ip.h"

#ifdef __cplusplus
extern "C"
{
#endif

#define UDP_HLEN 8

/* Fields are (of course) in network byte order. */
#ifdef PACK_STRUCT_USE_INCLUDES
#  include "arch/bpstruct.h"
#endif
  PACK_STRUCT_BEGIN struct udp_hdr
  {
    PACK_STRUCT_FIELD (u16_t src);
    PACK_STRUCT_FIELD (u16_t dest);	/* src/dest UDP ports */
    PACK_STRUCT_FIELD (u16_t len);
    PACK_STRUCT_FIELD (u16_t chksum);
  } PACK_STRUCT_STRUCT;
    PACK_STRUCT_END
#ifdef PACK_STRUCT_USE_INCLUDES
#  include "arch/epstruct.h"
#endif
#define UDP_FLAGS_NOCHKSUM 0x01U
#define UDP_FLAGS_UDPLITE  0x02U
#define UDP_FLAGS_CONNECTED  0x04U
    struct udp_pcb
  {
/* Common members of all PCB types */
    IP_PCB;

/* Protocol specific PCB members */

    struct udp_pcb *next;

    u8_t flags;
    /* ports are in host byte order */
    u16_t local_port, remote_port;

#if LWIP_IGMP
    /* outgoing network interface for multicast packets */
    struct ip_addr multicast_ip;
#endif				/* LWIP_IGMP */

#if LWIP_UDPLITE
    /* used for UDP_LITE only */
    u16_t chksum_len_rx, chksum_len_tx;
#endif				/* LWIP_UDPLITE */

    /* receive callback function
     * addr and port are in same byte order as in the pcb
     * The callback is responsible for freeing the pbuf
     * if it's not used any more.
     *
     * @param arg user supplied argument (udp_pcb.recv_arg)
     * @param pcb the udp_pcb which received data
     * @param p the packet buffer that was received
     * @param addr the remote IP address from which the packet was received
     * @param port the remote port from which the packet was received
     */
    void (*recv) (void *arg, struct udp_pcb * pcb, struct pbuf * p,
		  struct ip_addr * addr, u16_t port);
    /* user-supplied argument for the recv callback */
    void *recv_arg;
  };
/* udp_pcbs export for exernal reference (e.g. SNMP agent) */
  extern struct udp_pcb *udp_pcbs;

/* The following functions is the application layer interface to the
   UDP code. */
  struct udp_pcb *udp_new (void);
  void udp_remove (struct udp_pcb *pcb);
  err_t udp_bind (struct udp_pcb *pcb, struct ip_addr *ipaddr, u16_t port);
  err_t udp_connect (struct udp_pcb *pcb, struct ip_addr *ipaddr, u16_t port);
  void udp_disconnect (struct udp_pcb *pcb);
  void udp_recv (struct udp_pcb *pcb,
		 void (*recv) (void *arg, struct udp_pcb * upcb,
			       struct pbuf * p,
			       struct ip_addr * addr,
			       u16_t port), void *recv_arg);
  err_t udp_sendto_if (struct udp_pcb *pcb, struct pbuf *p,
		       struct ip_addr *dst_ip, u16_t dst_port,
		       struct netif *netif);
  err_t udp_sendto (struct udp_pcb *pcb, struct pbuf *p,
		    struct ip_addr *dst_ip, u16_t dst_port);
  err_t udp_send (struct udp_pcb *pcb, struct pbuf *p);

#define          udp_flags(pcb)  ((pcb)->flags)
#define          udp_setflags(pcb, f)  ((pcb)->flags = (f))

/* The following functions are the lower layer interface to UDP. */
  void udp_input (struct pbuf *p, struct netif *inp);

#define udp_init()		/* Compatibility define, not init needed. */

#if UDP_DEBUG
  void udp_debug_print (struct udp_hdr *udphdr);
#else
#define udp_debug_print(udphdr)
#endif

#ifdef __cplusplus
}
#endif

#endif				/* LWIP_UDP */

#endif				/* __LWIP_UDP_H__ */
